Cylinder liner, apparatus for extracting a cylinder liner and method for extracting a cylinder liner

Abstract

Cylinder liner for an internal combustion engine, comprising: a cylindrical portion having an outer diameter and an inner diameter, the inner diameter at least partly realizing a cylinder wall, when the cylinder liner is mounted in the internal combustion engine, a circumferential recess at the inner diameter of the cylindrical portion having a larger diameter than the inner diameter of the cylinder wall, wherein the circumferential recess is located at one end of the cylindrical portion, and a removable scraper ring,
wherein the recess comprises at least one groove, wherein a size of the scraper ring is adapted to fit into the recess and to cover the at least one groove.

Claims

1. A system, comprising: a tool configured to extract a cylinder liner from a crankcase of an internal combustion engine, wherein the tool comprises: a carrier portion; an adjustment portion being arranged at the carrier portion; a pulling portion being connected with the adjustment portion and/or the carrier portion; at least one central segment being adjustably connected with the adjustment portion; at least two outer segments, each comprising at least one gripper portion; wherein the adjustment portion is configured to shift a position of the at least one central segment in a longitudinal direction relative to the carrier portion to transfer a force to the at least two outer segments to drive a radial movement of the at least two outer segments, wherein the at least one gripper portions of the at least two outer segments are shaped to fit into at least one groove of the cylinder liner.

2. The system of claim 1, comprising: the cylinder liner for the internal combustion engine, comprising: a cylindrical portion having an outer diameter and an inner diameter, wherein the inner diameter at least partly defines a cylinder wall when the cylinder liner is mounted in the internal combustion engine; a circumferential recess at the inner diameter of the cylindrical portion, wherein the circumferential recess comprises a diameter larger than the inner diameter of the cylinder wall, wherein the circumferential recess is located at one end of the cylindrical portion, and a removable scraper ring; wherein the circumferential recess comprises the at least one groove, wherein a size of the removable scraper ring is adapted to fit into the circumferential recess and to cover the at least one groove.

3. The system according to claim 2, comprising the internal combustion engine having the cylinder liner.

4. The system according to claim 1, wherein the adjustment portion and/or the carrier portion are configured to guide a position of the at least two outer segments in a longitudinal direction and/or in a radial direction.

5. The system according to claim 1, wherein the pulling portion is configured to be connected with a lift.

6. A method for extracting the cylinder liner from the crankcase of the internal combustion engine with the tool according to claim 1, comprising the following steps: removing a removable scraper ring from a circumferential recess of the cylinder liner, wherein the circumferential recess comprises the at least one groove, placing the tool in an area of the circumferential recess such that the at least one gripper portion substantially lines up with the at least one groove in the longitudinal direction of the cylinder liner; adjusting the adjustment portion to transfer the force to the at least two outer segments to drive the radial movement of the at least two outer segments until the at least one gripper portion radially engages with the at least one groove; and, extracting the cylinder liner by use of the pulling portion of the tool.

7. The system according to claim 1, wherein the at least one central segment comprises a first conical surface, and the at least two outer segments comprise a second conical surface.

8. The system according to claim 7, wherein the adjustment portion is configured to shift a position of the at least one central segment in the longitudinal direction relative to the carrier portion to cause the radial movement of the at least two outer segments by a sliding action between the first and second conical surfaces.

9. A system, comprising: a cylinder liner, comprising a cylindrical portion having an outer diameter and an inner diameter, wherein the inner diameter at least partly defines a cylinder wall for a reciprocating piston; a circumferential recess at the inner diameter of the cylindrical portion, wherein the circumferential recess comprises a diameter larger than the inner diameter of the cylinder wall; at least one groove in the circumferential recess; and a removable scraper ring configured to fit into the circumferential recess and to cover the at least one groove; and a tool configured to extract the cylinder liner from a machine, wherein the tool comprises: a central segment; and a plurality of outer segments, wherein the central segment is configured to move in an axial direction to transfer a force to the plurality of outer segments to drive the plurality of outer segments in a radial direction into the at least one groove.

10. The system of claim 9, wherein the at least one groove is disposed at an end portion of the cylindrical portion, and the circumferential recess and the at least one groove are disposed at a flange of the cylindrical portion.

11. The system of claim 9, wherein an inner diameter of the removable scraper ring is the same as the inner diameter of the cylindrical portion, wherein a longitudinal length of the removable scraper ring is the same as a longitudinal length of the cylindrical portion along longitudinal axes of the removable scraper ring and the cylindrical portion, respectively.

12. The system of claim 9, wherein the tool is configured to extract the cylinder liner from the machine while the reciprocating piston remains in the machine.

13. The system of claim 9, comprising the machine having the cylinder liner and the reciprocating piston disposed in the cylinder liner.

14. The system of claim 9, wherein the tool is configured to transfer the force via mating surfaces that slide along one another between the central segment and the plurality of outer segments.

15. The system of claim 14, wherein the mating surfaces comprises first and second tapered surfaces.

16. A system, comprising: a tool configured to extract a cylinder liner from a machine, wherein the tool comprises: a central segment; and a plurality of outer segments, wherein the central segment is configured to move in an axial direction to transfer a force to the plurality of outer segments to drive the plurality of outer segments in a radial direction into at least one groove in the cylinder liner.

17. The system of claim 16, wherein the tool is configured to transfer the force via mating surfaces that slide along one another between the central segment and the plurality of outer segments.

18. The system of claim 17, wherein the mating surfaces comprises first and second tapered surfaces.

19. The system of claim 17, wherein the mating surfaces comprises first and second conical surfaces.

20. The system of claim 16, comprising the cylinder liner having the at least one groove within a circumferential recess in the cylinder liner, wherein a removable scraper ring is disposed in the circumferential recess over the at least one groove, and the circumferential recess is disposed at an end portion of the cylinder liner.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further details and advantages of the invention are apparent from the accompanying figures and the following description of the drawings. The figures show:

(2) FIG. 1 illustrates the internal combustion engine 1 having a cylinder liner according to a first embodiment of the invention,

(3) FIG. 2 illustrates the top portion of the cylinder liner of FIG. 1,

(4) FIG. 3 illustrates the enlarged detail D of FIG. 2,

(5) FIG. 4 illustrates the cylinder liner of FIG. 1 with removed scraper ring,

(6) FIG. 5 illustrates the cylinder liner of FIG. 1 with attached apparatus for extracting a cylinder liner, and

(7) FIGS. 6 and 7 illustrate the removed power unit with attached apparatus.

DETAILED DESCRIPTION

(8) FIG. 1 shows an internal combustion engine 1 having a cylinder liner according to a first embodiment of the invention.

(9) As can be seen, the cylinder liner 2 is mounted in the internal combustion engine 1, in more detail at the crankcase 3 of the internal combustion engine 1. The internal combustion engine 1 shown by FIG. 1 is in a state of maintenance work, wherein the power unit 4 is going to be removed.

(10) The power unit 4 comprises the cylinder liner 3, the piston 5 and the connecting rod 6. Beside these main elements of the power unit 4 also small parts as the piston pin, the piston rings and so on are included, which are not mentioned further here.

(11) It can be seen in this FIG. 1 that it is not possible to remove the connecting rod 6 and therefore the piston 5 through the cylinder liner 2, because the dimensions of the connecting rod 6 are too big to fit through the inner diameter of the cylinder liner 2. Therefore, the power unit 4 has to be removed as a whole, wherein the power unit 4 can be disassembled after removing from the crankcase 3 of the internal combustion engine 1.

(12) In this context, in a first step (as shown by FIG. 1), the connecting rod 6 has to be removed from the crankshaft 7 and the cylinder head has to be removed from the internal combustion engine 1 and from the cylinder liner 2

(13) The piston 5 and the connected connecting rod 6 are pressed back into a position, in which an area of the recess 8 of the cylinder liner 2 and the scraper ring 9 (which is arranged in the recess 8) are released.

(14) This can be seen in more detail in FIG. 2, wherein the top portion of the cylinder liner 2 arranged in the crankcase 3 can be seen. FIG. 3 discloses the enlarged detail D of FIG. 2.

(15) As can be seen, the size of the scraper ring 9 is adapted to fit into the recess 8 of the cylinder liner 2, wherein the groove 10 of the cylinder liner 2 is covered by the scraper ring 9.

(16) The cylinder liner 2 of this embodiment is designed as a top-stop liner as can be seen by the flange 11, which is provided at an end of the cylinder liner 2 facing the cylinder head in a mounted state in the internal combustion engine 1.

(17) The recess 8 is arranged in an area of a flange 11 of the cylinder liner 2, wherein the flange 11 is arranged at a top end of the cylindrical portion facing a cylinder head of the internal combustion engine 1 when the cylinder liner 2 is mounted in the internal combustion engine 1.

(18) The recess 8 is arranged circumferentially at the inner diameter of the cylindrical portion of the cylinder liner 2 having a larger diameter than the inner diameter of the cylinder wall, wherein the circumferential recess 8 is located at one end of the cylinder liner 2 facing the cylinder head in a mounted state inside the internal combustion engine 1.

(19) The scraper ring 9 covers the whole circumferential recess 8 in a direction of the inner diameter of the cylinder liner 2, when the at least one removable scraper ring 9 is arranged in the recess 8.

(20) The scraper ring 9 comprises an inner diameter having the same diameter as the inner diameter of the cylinder liner 2 and the scraper ring 9 has essentially the same longitudinal length in direction parallel to a centerline 12 of the scraper ring 9 as a longitudinal length of the circumferential recess 8 in direction parallel to a centerline 12 of the cylinder liner 2.

(21) In a next step to remove the power unit 4, the scraper ring 9 is removed from the cylinder liner 2 as shown by FIG. 4. By removing the scraper ring 9, the recess 8 and the circumferential groove 10 at the inner diameter of the recess 8 are released.

(22) In a next step (as shown by FIG. 5), an apparatus 13 for extracting a cylinder liner 2 from a crankcase 3 of an internal combustion engine 1 is placed in the area of the flange 11, such that the gripper portions 18 of the apparatus 13 substantially line up with the at least one groove 10 in a longitudinal direction of the cylinder liner 2.

(23) The apparatus 13 comprises a carrier portion 14, an adjustment portion 15 being arranged at the carrier portion 14, a central segment 16, and at least two outer segments 17 each comprising at least one gripper portion 18.

(24) The adjustment portion 15 is configured to shift the position of the central segment 16 in a longitudinal direction relative to the carrier portion 14, such that said shift leads to a radial movement of the at least two outer segments 17.

(25) The adjustment portion 15 of this embodiment is designed as an adjustment screw, which engages with a thread on an adjusting nut 21 on the carrier portion 14. By screwing the adjustment portion 15, the adjustment portion 15 can be moved (together with the central segment 16 attached to the adjustment portion 15) in a longitudinal direction relative to the carrier portion 14.

(26) By the sliding action between the central segment 16 and the at least two outer segments 17 (at the conical contact surfaces), this longitudinal movement is transformed into a radial movement of the at least two outer cone segments 17. In this way, the radial position of the at least two outer cone segments 17 can be varied by the adjustment portion 15, wherein the at least two outer cone segments 17 can be moved in a position, wherein the gripping portions 18 of the outer segments 17 engage into the groove 10 of the cylinder liner 2.

(27) The gripper portions 18 of the at least two outer segments 17 are shaped to fit into the groove 10 of the cylinder liner 2.

(28) Furthermore, the apparatus 13 comprises a pulling portion 19, which is configured to be connected with a lifting device by a pulling eye 20.

(29) In a next step, the cylinder liner 2 (together with the whole power unit 4) can be removed from the crankcase 3 using the pulling portion 19.

(30) In FIGS. 6 and 7, the removed power unit 4 with attached apparatus can be seen.

LIST OF REFERENCE SIGNS

(31) 1 internal combustion engine 2 cylinder liner 3 crankcase 4 power unit 5 piston 6 connecting rod 7 crankshaft 8 recess 9 scraper ring 10 groove 11 flange 12 centerline 13 apparatus 14 carrier portion 15 adjustment portion 16 central segment 17 outer segment 18 gripper portion 19 pulling portion 20 pulling eye 21 adjusting nut